Principal, Machine Learning Engineer (L5)
Twilio · Posted Oct 8
Cloud-based customer engagement platform providing APIs for messaging, voice, email, and customer data orchestration
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About the role
Twilio's Customer Memory Team builds the foundational AI/ML capabilities that power intelligent engagement experiences, letting any application, human or AI agent, or channel know who a customer is, what they have done, and how best to reach them. The work spans contextual intelligence, LLM orchestration, retrieval strategies, and large-scale machine learning systems. This role leads rapid research cycles and production-grade experimentation to deliver enterprise-quality personalized engagement at Twilio scale.
What you will do
- Build out new functionality within a fast moving product seeing rapid adoption.
- Take a nebulous idea, design a rigorous experiment, and execute it within weeks.
- Conduct deep-dive research into state-of-the-art LLM orchestration, retrieval strategies, and data-driven personalization.
- Build ML systems that hold up at Twilio scale.
- Rapidly acquire new technical skills and knowledge in a fast-paced, high-delivery environment.
- Proactively leverage and integrate the latest AI development stacks to bypass boilerplate engineering and focus on core differentiation.
Skills used in this role
What the employer is looking for
- 10+ years applied ML/AI experience with a track record of owning technically ambitious systems end to end rather than contributing to someone else's design.
- Comfort operating in a 0-to-1 setting with ambiguous requirements and a strong bias for action.
- Proficiency in Python programming language.
- Experience building cloud-based services on AWS, GCP, or Azure, with high-volume data, streaming or real-time inference paths, and a range of data stores.
- Deep expertise in the design, architecture, and deployment of production-grade ML/AI systems, including LLM orchestration, embedding models, and vector stores.
- Strong fundamentals of statistical machine learning algorithms, transformer models, LLMs
- Ability to raise the technical bar of a team through mentorship, design review, and standards, without formal management authority.
- Experience in building cloud-based services using AWS, GCP, or Azure.
- Strong communication skills and highly effective collaborator who works well with teammates.
Preferred qualifications
- Prior experience building autonomous agents that handle multi-turn conversations and maintain long-term context/consistency.
- Strong background in predictive modeling on user behavior, including experiment design and the causal or counterfactual methods needed when randomization is partial.
- Prior experience working in a globally distributed team.
Benefits and support
- generous time off
- parental and wellness leave
- healthcare
- retirement savings program
About Twilio
Twilio is a cloud communications platform-as-a-service company that allows software developers to programmatically make and receive phone calls, send and receive text messages, and perform other communication functions using its web service APIs. The company also offers customer engagement software and a customer data platform, Twilio Segment, to help businesses personalize interactions at scale. Today, it operates as a key infrastructure provider powering digital communications for brands worldwide.
- Industry
- Cloud Communications
- Company size
- 5000-10000 employees
- Founded
- 2008
- Location
- San Francisco, California, USA
- Funding stage
- Public Company
Funding
Public Company · $240M raised
- 2021-07-31Post IPO Debt
- 2018-05-01Post IPO Equity
- 2015-07-31Series E
Leadership
Chief Executive Officer
Chief Financial Officer
Chief Administrative Officer
President, Twilio Segment / Chief Revenue Officer
Chief Marketing Officer
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